


rotted kinktober.

by Anonymous



Category: Undertale (Video Game)
Genre: M/M, please dont read if youre uncomfortable with the tags already, some unhealthy, these are just my own fantasies
Language: English
Status: In-Progress
Published: 2019-10-28
Updated: 2019-10-31
Packaged: 2021-01-06 01:09:25
Rating: Not Rated
Warnings: Rape/Non-Con, Underage
Chapters: 5
Words: 2,078
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21218054
Author URL: https://archiveofourown.org/
Summary: just a bit late.also, please note the tags i already have up. these are JUST fantasies, and some are very unhealthy. i just wanted to explore with writing them.





	1. day one: piss and fear

**Author's Note:**

> yeah uh
> 
> just a note, reader is trans and sans respects that.
> 
> kay thanks

You swallowed nervously as he pinned you against the wall.

You two had been dancing- or more like he was giving you lessons on how to not be as clumsy as hell- but.. you started getting more confident, pressing yourself against him as you got lost in the beat and rhythm.

But now you were so fucking embarrassed. You swallowed again as he leaned closer, sniffing at you. "..heh. if you wanted to be boned so bad.." He shoved a knee between your legs, gripping the front of your shirt to pull you close and slam his teeth against your lips. You tried recoiling, cringing. It hurt. But he only gripped you tighter, pressing his knee firmly against your crotch.

"S-stop--" You tried pleading. You.. you weren't comfortable with having him see you. Besides, you were.. rather ashamed of your body.

He didn't listen to you, tongue forcing its way into your mouth. You decided to go slack, hating the little thrill you got from this. From.. being used.

But it still felt terrible. You were a virgin, and.. and you were only seventeen. You knew Sans was somewhere in his twenties, but.. If you were so close to being eighteen, it wasn't all that bad.. right?

"god. you really are a little whore, aint ya?" He chuckled, pulling away to lave his tongue down your neck. "so tense.. just relax and be a good boy. and maybe i'll give him a little treat."

You almost moaned, just from his voice and his tongue and the fucking pet name. You started grinding against his knee, hands clutching at his shirt. "P..please, Sans." The words coming out of your mouth fucking appalled you. It sent butterflies racing in your stomach, and your face was so warm.

"i can fuckin smell ya.. maybe i need to put something up your cunt, ya lil whore." He nipped at your neck and you whimpered.

You.. you wanted it. But what if it hurt? What if his dick was.. was way too big?

You were pretty damn small, standing at 4'11. He had practically thrown you against the wall, and the only thing keeping you up was his knee. 

"answer me." He bit down harder, and you struggled to get away from him. He only dug his teeth in deeper, a warning. "little whore. i know you want it. dont you dare run away."

You shut your eyes tight. You.. couldn't believe this was happening. Sure, you.. happened to have a damn huge crush on him, but this was too much for you. The butterflies had rotted away to acid.

You felt dirty.  
  
"I.. I want you to fuck me." The words were barely a whisper. You were trying so damn hard to keep your tears hidden from him.. you were shocked when he cooed softly. "good boy.. don't worry, okay? i think i should give you your present now." 

he slowly let you down, pushing on your shoulder firmly until you were on your knees. "i know you're so needy.." he muttered softly. "but maybe, when you're a bit bigger, little pup, i can give you what you want. but for now.."  
  
Sans let out a soft sigh as he pushed down his shorts just a bit and pulled his dick out. You cringed, watching as he rubbed his thumb over the head. It.. it was giant.

He chuckled at your terror. "relax.. m'not gonna make ya blow me. just wanna mark my territory.." His eyelights had vanished.

"keep still." That was the only warning you got before you felt something warm splash in your hair. Your eyes widened and you started shaking. You couldn't.. believe this.

He was fucking pissing on you. It felt so fucking.. humiliating. But you loved it. You loved how he was using you.

You felt dirty, and it made you so fucking turned on. You clutched your hands, trying to ignore the throbbing in your pussy.

Finally, he let out a sigh, and tucked his dick back into his pants. "now get out and go get cleaned up." he said, laying a hand on your cheek. "but dont you dare try removing my scent. you're mine, little pup. and i'm never ever gonna lose ya to someone else.


	2. day two: obsessive love

**Summary for the Chapter:**

> you can't stay away from him

It had been a week after he pissed on you.

Thinking about it always made you fo fucking worked up. You'd break out in goosebumps, and you just had the need to be.. filled. Used.

You wanted more. So you went back after avoiding him.

He was dancing alone when you got there, so you just hid, peeking into the room. He was so graceful and mesmerizing and.. just so magnetic. The butterflies started up in your stomach again, and you decided to stop snooping in on him. You hesitated before letting your hand snake down into your sweats, rubbing yourself through your underwear. You shivered, biting your lip as you tried peeking into the room again.

Thank god, he hadn't noticed you. He was still dancing, a serene smile on his face. Your heart fluttered.. _maybe he'd make that face around you?_

God, you.. you might risk it and say you're in love with him. Your heart started racing, pulled from your thoughts, as he turned his head and winked at you. "wonder when you'd show up again." he purred, turning around and going to turn down the speakers that were blasting music.

The butterflies slowly died off again, rotting. You swallowed thickly, tearing your hand out of your pants.

"you aren't very subtle."

You cringed as he beckoned you forward, staring at the ground as you drug your feet to him. He smiled softly, petting your hair. "i've missed you.." he said softly, kissing your forehead. 

"and i saw you touching yourself, little pup.." He tsked, gently tugging your hair. "would like if you gave me a show." One of his hands ran up your shirt, being careful to avoid your chest. The butterflies started up again, and a shy smile curled on your face. He was so nice..

"..Okay." You stammered out, hands clutching at his shirt again. He nuzzled your cheek, hands trailing down to your ass. He pressed you against him, rolling his hips against you. "see what you do to me, little pup?" He murmured softly. "can't wait until i can fully make you mine.."

The words made you shiver. You knew he was using you, and you were such a slut for liking it. But.. you were his slut.

His little pup.


	3. day three: rape/somnophilia

**Summary for the Chapter:**

> you've snuck over to sans's house

Sans stood over your sleeping form. You were curled up in a ball, face twisted in a frown. You were.. probably having a nightmare. He sighed, looking back to make sure the door was locked before crawling on the bed. He knelt beside you so you were facing him, and he pulled his dick from his pants. He was already half hard from watching you squirm and whimper.

He sighed, slowly rubbing himself as he pressed the head against your lips. With a gentle shove, the head was inside your mouth and resting on your tongue. He let out a soft groan, gently rocking back and forth.

He knew you had woken up, with how your face scrunched up and your eyelids fluttered. It was like you were trying to convince him you were still asleep. Your hands were clenched against your thighs, nails digging into your skin.

"suck." he demanded, grabbing a fistful of your hair.

You blinked back tears, deciding to listen to him.

You were his little pup, and you wanted to prove how good you could be to him. He was your master, and you didn't wanna lose his love.


	4. day four: tentacles/praise kink

**Summary for the Chapter:**

> something happier

**Notes for the Chapter:**

> both reader and sans are 17.
> 
> ut sans this time, though its lowkey my own take on him. still the same to normal ut sans tho

You squirmed in the hold of Sans' magic, sticking your tongue out at him. "That's not how cheese-touch works!" You complained childishly. He tsk'ed, patting your head. "street rules, babe. besides, i've never played it." He shrugged. "not familiar with every human thing out there."

You froze, staring at him. "You mean you've never read diary of a wimpy kid?"

He scrunched up his face, shaking his head. "hey, i respect your privacy. i'd never do that." His mouth twitched - he was struggling to hide a smug smirk. You tried wriggling closer to him, stretching out your head in an attempt to touch him. "I'll give you double cheese-touch this time." You threatened.

He shrugged, simply scooting further from your place on the floor. "better get comfy." He leaned back against the wall, cracking open his weird book-inside-book thing. You stared at him, eyes narrowing before you gave up your struggle, letting your cheek lay on the carpet.

..Honestly? It was kinda comfy. You yawned, starting to relax as you felt something massaging into your back. "i said get comfy, babe. you lost fair and square." He looked at you over the top of his book, grin wide and a bit predatory. "now it's time for my prize."

You were going to shoot back a snarky remark at him before he shoved a tentacle in your mouth. Your eyes widened and you shuddered, glaring at him as a blush flooded your face.

Sure, you two had had sex plenty of times before, but it always made you shy and embarrassed. He always respected your boundaries, though.

But he must have caught on to how horny you'd been recently, getting flustered so easily around him and leaving the room. It was kinda cute.. and flattering. After all, what did you even see in him? He was just a plain ol' skeleton.

Sans let out a sigh, closing his book and instead focusing on you as he slid a tentacle down your sweats, almost letting out a groan at the sight of you. You already looked wrecked, hips rolling back against the tentacle in an attempt to get it deeper. 

"adorable.." He mumbled, a thrill running through him at the sounds of your whimpers and, god, the smell of your arousal. Your eyes darting over to him and he grinned more, green eyelights bright. "such a good little boy.. you're so cute when you get all shy like that." he murmured softly, releasing the hold of his magic from you as he slowly slid down your sweats. He let out a groan, seeing how soaked you were.

He was going to make you feel amazing. He knew how insecure you got about your genitals ("but.. im not a full guy even." "do you really think i'd care? you're you. and i love you.") and he wanted so bad to see that that didn't matter.

He loved you for you. 

He removed his tentacles, letting out a quiet sigh. He knew his eyes had turned to hearts at the indignant look on your face, though it softened immediately as he cupped your face in his hands. "i fucking love you.." he murmured softly, grinding his still-clothed dick against you. "you've been such a good boy.. 's time for me to show how much i love you."


	5. day 5: obsessive love pt 2

**Summary for the Chapter:**

> you thought you were his.

You didn't know he had a girlfriend.

You felt bile rise in your throat as you stared at yourself in the mirror. You were rather skinny, though not malnourished. Maybe he was disgusted by how bony you were, or your eccentric personality.

_Maybe it's because she was old enough._

You lurched over the toilet and dry-heaved, clenching your eyes shut tight to try and keep tears away.

At.. at least he still bothered with you, right?

You hadn't transitioned yet. You could still be his perfect little pup. You'd do anything for him. Maybe he likes you how you are now?

You drag your fingers down your face, body shaking with quiet sobs. You flinched as your phone started vibrating a moment later.

You stared at it, fists clenching and relaxing before you drug your feet over to the bed. Your heart did a flip as soon as you saw who was calling you, and you cleared your throat in an attempt to make yourself sound semi-normal.

"come over." his voice was rough. And he sounded so fucking wrecked... had he just fucked her?

"Why?" You couldn't help but snap back at him, your eyes burning again. "You obviously sound busy, so--"

  
  
"pup." He didn't leave any room for you to argue. "come over. now."

He hung up. Shoulders slumping, you got up to put some clothes back on. And, pausing, you threw a blanket over the mirror before heading out.


End file.
